Sort and Merge

 The StudentFile is a sequential file sequenced upon ascending StudentId.  Write a program to display the number of students taking each course. How? DATA DIVISION. FILE SECTION. FD StudentFile. 01 StudentDetails. 02 StudentId PIC 9(7). 02 StudentName. 03 Surname PIC X(8). 03 Initials PIC XX. 02 DateOfBirth. 03 YOBirth PIC 9(2). 03 MOBirth PIC 9(2). 03 DOBirth PIC 9(2). 02 CourseCode PIC X(4). 02 Grant PIC 9(4). 02 Gender PIC X.

Simplified Sort Syntax.  The WorkFileName identifies a temporary work file that the SORT process uses for the sort. It is defined in the FILE SECTION using an SD entry.  Each SortKeyIdentifier identifies a field in the record of the work file upon which the file will be sequenced.  When more than one SortKeyIdentifier is specified, the keys decrease in significance from left to right (leftmost key is most significant, rightmost is least significant).  InFileName and OutFileName, are the names of the input and output files. These files are automatically opened by the SORT. When the SORT executes they must not be already open.

FD SalesFile. 01 SalesRec. 02 FILLERPIC X(10). WorkFile WSalesmanNum SD WorkFile. 01 WorkRec. 02 WSalesmanNumPIC 9(5). 02 FILLER PIC X(5). FD SortedSalesFile. 01 SortedSalesRec. 02 SalesmanNumPIC 9(5). 02 ItemTypePIC X. 02 QtySoldPIC 9(4). WorkFileWSalesmanNum PROCEDURE DIVISION. Begin. SORT WorkFile ON ASCENDING KEY WSalesmanNum USING SalesFile GIVING SortedSalesFile. OPEN INPUT SortedSalesFile. Sort Example.

ENVIRONMENT DIVISION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT WorkFile ASSIGN TO "WORK.TMP". SD WorkFile. 01 WorkRecord. 02 ProvinceCode PIC SalesmanCode PIC 9(5). 02 FILLER PIC X(19). PROCEDURE DIVISION. Begin. SORT WorkFile ON ASCENDING KEY ProvinceCode DESCENDING KEY SalesmanCode USING UnsortedSales GIVING SortedSales. OPEN INPUT SortedSales. ENVIRONMENT DIVISION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT WorkFile ASSIGN TO "WORK.TMP". SD WorkFile. 01 WorkRecord. 02 ProvinceCode PIC SalesmanCode PIC 9(5). 02 FILLER PIC X(19). PROCEDURE DIVISION. Begin. SORT WorkFile ON ASCENDING KEY ProvinceCode DESCENDING KEY SalesmanCode USING UnsortedSales GIVING SortedSales. OPEN INPUT SortedSales.

SORTProcess WorkFile How the SORT works. SORT WorkFile ON ASCENDING KEY WSalesmanNum USING SalesFile GIVING SortedSalesFile. SalesFileSortedSalesFile Unsorted Records Sorted Records

SORTProcess How the INPUT PROCEDURE works. SORT WorkFile ON ASCENDING KEY WSalesmanNum INPUT PROCEDURE IS SelectHatSales GIVING SortedSalesFile. WorkFile SalesFileSortedSalesFile Sorted Records SelectHatSales Unsorted Hat Records Unsorted Records

OPEN INPUT InFileName READ InFileName RECORD PERFORM UNTIL Condition RELEASE SDWorkRec READ InFileName RECORD END-PERFORM CLOSE InFile OPEN INPUT InFileName READ InFileName RECORD PERFORM UNTIL Condition RELEASE SDWorkRec READ InFileName RECORD END-PERFORM CLOSE InFile INPUT PROCEDURE Template

FD SalesFile. 01 SalesRec. 88 EndOfSales VALUE HIGH-VALUES. 02 FILLERPIC 9(5). 02 FILLERPIC X. 88 HatRecord VALUE "H". 02 FILLERPIC X(4). SD WorkFile. 01 WorkRec. 02 WSalesmanNumPIC 9(5). 02 FILLERPIC X(5). FD SortedSalesFile. 01 SortedSalesRec. 02 SalesmanNumPIC 9(5). 02 ItemTypePIC X. 02 QtySoldPIC 9(4). SelectHatSales PROCEDURE DIVISION. Begin. SORT WorkFile ON ASCENDING KEY WSalesmanNum INPUT PROCEDURE IS SelectHatSales GIVING SortedSalesFile. FD SalesFile. 01 SalesRec. 88 EndOfSales VALUE HIGH-VALUES. 02 FILLERPIC 9(5). 02 FILLERPIC X. 88 HatRecord VALUE "H". 02 FILLERPIC X(4). SD WorkFile. 01 WorkRec. 02 WSalesmanNumPIC 9(5). 02 FILLERPIC X(5). FD SortedSalesFile. 01 SortedSalesRec. 02 SalesmanNumPIC 9(5). 02 ItemTypePIC X. 02 QtySoldPIC 9(4). SelectHatSales PROCEDURE DIVISION. Begin. SORT WorkFile ON ASCENDING KEY WSalesmanNum INPUT PROCEDURE IS SelectHatSales GIVING SortedSalesFile. INPUT PROCEDURE - Example

New Version SelectHatSales. OPEN INPUT SalesFile READ SalesFile AT END SET EndOfSales TO TRUE END-READ PERFORM UNTIL EndOfSales IF HatRecord RELEASE WorkRec FROM SalesRec END-IF READ SalesFile AT END SET EndOfSales TO TRUE END-READ END-PERFORM CLOSE SalesFile. SelectHatSales. OPEN INPUT SalesFile READ SalesFile AT END SET EndOfSales TO TRUE END-READ PERFORM UNTIL EndOfSales IF HatRecord RELEASE WorkRec FROM SalesRec END-IF READ SalesFile AT END SET EndOfSales TO TRUE END-READ END-PERFORM CLOSE SalesFile.

Old Version SelectHatSales SECTION. BeginHatSales. OPEN INPUT SalesFile READ SalesFile AT END SET EndOfSales TO TRUE END-READ PERFORM GetHatSales UNTIL EndOfSales CLOSE SalesFile GO TO SelectHatSalesExit. GetHatSales. IF HatRecord RELEASE WorkRec FROM SalesRec END-IF READ SalesFile AT END SET EndOfSales TO TRUE END-READ. SelectHatSalesExit EXIT. SelectHatSales SECTION. BeginHatSales. OPEN INPUT SalesFile READ SalesFile AT END SET EndOfSales TO TRUE END-READ PERFORM GetHatSales UNTIL EndOfSales CLOSE SalesFile GO TO SelectHatSalesExit. GetHatSales. IF HatRecord RELEASE WorkRec FROM SalesRec END-IF READ SalesFile AT END SET EndOfSales TO TRUE END-READ. SelectHatSalesExit EXIT.

ENVIRONMENT DIVISION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT WorkFile ASSIGN TO "WORK.TMP". SD WorkFile. 01 WorkRecord. 88 EndOfWorkFile VALUE HIGH-VALUES. 02 ProvinceCode PIC ProvinceIsUlster VALUE SalesmanCode PIC 9(5). 02 FILLER PIC X(19). FD UnsortedSales. 01 FILLER PIC X(25). FD SortedSales. 01 SortedRec. 88 EndOfSalesFile VALUE HIGH-VALUES. 02 ProvinceCode PIC SalesmanCode PIC 9(5). 02 ItemCode PIC 9(7). 02 ItemCost PIC 9(3)V QtySold PIC 9(7). ENVIRONMENT DIVISION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT WorkFile ASSIGN TO "WORK.TMP". SD WorkFile. 01 WorkRecord. 88 EndOfWorkFile VALUE HIGH-VALUES. 02 ProvinceCode PIC ProvinceIsUlster VALUE SalesmanCode PIC 9(5). 02 FILLER PIC X(19). FD UnsortedSales. 01 FILLER PIC X(25). FD SortedSales. 01 SortedRec. 88 EndOfSalesFile VALUE HIGH-VALUES. 02 ProvinceCode PIC SalesmanCode PIC 9(5). 02 ItemCode PIC 9(7). 02 ItemCost PIC 9(3)V QtySold PIC 9(7).

PROCEDURE DIVISION. Begin. SORT WorkFile ON ASCENDING KEY ProvinceCode SalesmanCode INPUT PROCEDURE IS SelectUlsterRecs GIVING SortedSales. OPEN INPUT SortedSales. SelectUlsterRecs. OPEN INPUT UnsortedSales READ UnsortedSales INTO WorkRec AT END SET EndOfSalesFile TO TRUE END-READ PERFORM UNTIL EndOfSalesFile IF ProvinceIsUlster RELEASE WorkRec END-IF READ UnsortedSales INTO WorkRec AT END SET EndOfSalesFile TO TRUE END-READ END-PERFORM CLOSE UnsortedSales PROCEDURE DIVISION. Begin. SORT WorkFile ON ASCENDING KEY ProvinceCode SalesmanCode INPUT PROCEDURE IS SelectUlsterRecs GIVING SortedSales. OPEN INPUT SortedSales. SelectUlsterRecs. OPEN INPUT UnsortedSales READ UnsortedSales INTO WorkRec AT END SET EndOfSalesFile TO TRUE END-READ PERFORM UNTIL EndOfSalesFile IF ProvinceIsUlster RELEASE WorkRec END-IF READ UnsortedSales INTO WorkRec AT END SET EndOfSalesFile TO TRUE END-READ END-PERFORM CLOSE UnsortedSales

Full Sort Syntax.  ProcedureName is the name of a section or paragraph.

SummariseSales SORTProcess WorkFile How the OUTPUT PROCEDURE works. SORT WorkFile ON ASCENDING KEY WSalesmanNum USING SalesFile OUTPUT PROCEDURE IS SummariseSales. SalesFile SalesSummaryFile Unsorted Records Salesman Summary Record Sorted Records

OPEN OUTPUT OutFile RETURN SDWorkFile RECORD PERFORM UNTIL Condition WRITE OutRec RETURN SDWorkFile RECORD END-PERFORM CLOSE OutFile OUTPUT PROCEDURE Template

FD SalesFile. 01 SalesRec PIC X(10). SD WorkFile. 01 WorkRec. 88 EndOfWorkFile VALUE HIGH-VALUES. 02 WSalesmanNumPIC 9(5). 02 FILLERPIC X. 02 WQtySold PIC X(4). FD SalesSummaryFile. 01 SummaryRec. 02 SalesmanNumPIC 9(5). 02 TotalQtySoldPIC 9(6). SummariseSales PROCEDURE DIVISION. Begin. SORT WorkFile ON ASCENDING KEY WSalesmanNum USING SalesFile OUTPUT PROCEDURE IS SummariseSales. OPEN INPUT SalesSummaryFile. PERFORM PrintSummaryReport. FD SalesFile. 01 SalesRec PIC X(10). SD WorkFile. 01 WorkRec. 88 EndOfWorkFile VALUE HIGH-VALUES. 02 WSalesmanNumPIC 9(5). 02 FILLERPIC X. 02 WQtySold PIC X(4). FD SalesSummaryFile. 01 SummaryRec. 02 SalesmanNumPIC 9(5). 02 TotalQtySoldPIC 9(6). SummariseSales PROCEDURE DIVISION. Begin. SORT WorkFile ON ASCENDING KEY WSalesmanNum USING SalesFile OUTPUT PROCEDURE IS SummariseSales. OPEN INPUT SalesSummaryFile. PERFORM PrintSummaryReport. Output PROCEDURE - Example

SummariseSales. OPEN OUTPUT SalesSummaryFile RETURN WorkFile AT END SET EndOfWorkFile TO TRUE END-RETURN PERFORM UNTIL EndOfWorkFile MOVE WSalesmanNum TO SalesmanNum MOVE ZEROS TO TotalQtySold PERFORM UNTIL WSalesManNum NOT = SalesmanNum OR EndOfWorkFile ADD WQtySold TO TotalQtySold RETURN WorkFile AT END SET EndOfWorkFile TO TRUE END-RETURN END-PERFORM WRITE SummaryRec END-PERFORM CLOSE SalesSummaryFile. SummariseSales. OPEN OUTPUT SalesSummaryFile RETURN WorkFile AT END SET EndOfWorkFile TO TRUE END-RETURN PERFORM UNTIL EndOfWorkFile MOVE WSalesmanNum TO SalesmanNum MOVE ZEROS TO TotalQtySold PERFORM UNTIL WSalesManNum NOT = SalesmanNum OR EndOfWorkFile ADD WQtySold TO TotalQtySold RETURN WorkFile AT END SET EndOfWorkFile TO TRUE END-RETURN END-PERFORM WRITE SummaryRec END-PERFORM CLOSE SalesSummaryFile.

RELEASE and RETURN Syntax WriteRead

Feeding the SORT from the keyboard. SORT WorkFile ON ASCENDING KEY WStudentId INPUT PROCEDURE IS GetStudentDetails GIVING StudentFile. WorkFile StudentFile Sorted Student Records SORTProcess GetStudentDetails Unsorted Student Records COUGHLAN

ENVIRONMENT DIVISION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT StudentFile ASSIGN TO "SORTSTUD.DAT" ORGANIZATION IS LINE SEQUENTIAL. SELECT WorkFile ASSIGN TO "WORK.TMP". DATA DIVISION. FILE SECTION. FD StudentFile. 01 StudentDetails PIC X(32). SD WorkFile. 01 WorkRec. 02 WStudentId PIC 9(7). 02 FILLER PIC X(25). PROCEDURE DIVISION. Begin. SORT WorkFile ON ASCENDING KEY WStudentId INPUT PROCEDURE IS GetStudentDetails GIVING StudentFile. STOP RUN. GetStudentDetails. DISPLAY "Enter student details using template below." DISPLAY "Enter no data to end.". DISPLAY "NNNNNNNSSSSSSSSIIYYMMDDCCCCGGGGS". ACCEPT WorkRec. PERFORM UNTIL WorkRec = SPACES RELEASE WorkRec ACCEPT WorkRec END-PERFORM. ENVIRONMENT DIVISION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT StudentFile ASSIGN TO "SORTSTUD.DAT" ORGANIZATION IS LINE SEQUENTIAL. SELECT WorkFile ASSIGN TO "WORK.TMP". DATA DIVISION. FILE SECTION. FD StudentFile. 01 StudentDetails PIC X(32). SD WorkFile. 01 WorkRec. 02 WStudentId PIC 9(7). 02 FILLER PIC X(25). PROCEDURE DIVISION. Begin. SORT WorkFile ON ASCENDING KEY WStudentId INPUT PROCEDURE IS GetStudentDetails GIVING StudentFile. STOP RUN. GetStudentDetails. DISPLAY "Enter student details using template below." DISPLAY "Enter no data to end.". DISPLAY "NNNNNNNSSSSSSSSIIYYMMDDCCCCGGGGS". ACCEPT WorkRec. PERFORM UNTIL WorkRec = SPACES RELEASE WorkRec ACCEPT WorkRec END-PERFORM.

MERGE Syntax.  The Merge takes two or more identically sequenced files and combines them, according to the key values specified, to produce a combined file which is then output to an output file or OUTPUT PROCEDURE.  e.g. MERGE WorkFile ON ASCENDING KEY StudentId USING InsertionsFile, StudentFile GIVING NewStudentFile.

ENVIRONMENT DIVISION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT StudentFile ASSIGN TO "STUDENTS.DAT" ORGANIZATION IS LINE SEQUENTIAL. SELECT InsertionsFile ASSIGN TO "TRANSINS.DAT" ORGANIZATION IS LINE SEQUENTIAL. SELECT NewStudentFile ASSIGN TO "STUDENTS.NEW" ORGANIZATION IS LINE SEQUENTIAL. SELECT WorkFile ASSIGN TO "WORK.TMP". DATA DIVISION. FILE SECTION. FD StudentFile. 01 StudentRec PIC X(32). FD InsertionsFile. 01 InsertionRec PIC X(32). FD NewStudentFile. 01 NewStudentRec PIC X(32). SD WorkFile. 01 WorkRec. 02 WStudentId PIC 9(7). 02 FILLER PIC X(25). PROCEDURE DIVISION. Begin. MERGE WorkFile ON ASCENDING KEY WStudentId USING InsertionsFile, StudentFile GIVING NewStudentFile. STOP RUN. ENVIRONMENT DIVISION. INPUT-OUTPUT SECTION. FILE-CONTROL. SELECT StudentFile ASSIGN TO "STUDENTS.DAT" ORGANIZATION IS LINE SEQUENTIAL. SELECT InsertionsFile ASSIGN TO "TRANSINS.DAT" ORGANIZATION IS LINE SEQUENTIAL. SELECT NewStudentFile ASSIGN TO "STUDENTS.NEW" ORGANIZATION IS LINE SEQUENTIAL. SELECT WorkFile ASSIGN TO "WORK.TMP". DATA DIVISION. FILE SECTION. FD StudentFile. 01 StudentRec PIC X(32). FD InsertionsFile. 01 InsertionRec PIC X(32). FD NewStudentFile. 01 NewStudentRec PIC X(32). SD WorkFile. 01 WorkRec. 02 WStudentId PIC 9(7). 02 FILLER PIC X(25). PROCEDURE DIVISION. Begin. MERGE WorkFile ON ASCENDING KEY WStudentId USING InsertionsFile, StudentFile GIVING NewStudentFile. STOP RUN.